I remember seeing some links on the forum that point to studies that reached different conclusions, but I failed to find them with my lame search skill (was there a discussion thread a little while back suggesting that the heart tissue scarring and damages...etc were shown only in the really elite/dedicate runners?) Thanks for any pointers to anything useful.

The problem with the article is that it suggests that training for anything near and over the marathon distance is bad for you.

"The authors surveyed more than 50 different studies that followed athletes who chronically trained and participated in extreme endurance events, such as marathons, ultramarathons, Ironman triathlons, and long-distance bicycle races. The studies found that excessive training and competing can cause cardiovascular damage such as scarring and enlargement of the heart and blood vessels, as well as irregular heart beating."

It did not really quantify what it means by "chronically trained and participated in extreme endurance events". What this means is someone can (and did) just read this and point it to me and say "you're doing marathon training and it is bad for you". And of course I lack the Mayo clinics credential to argue otherwise.

There are lots of them out there that are from lesser known people but these should stand up to scrutiny.

If you look hard enough you can find a study that proves just about anything is bad for you. Drinking water was a huge one I remember. But if you read the study you had to drink like 20 Litres in 10 mins.

People love the giant headlines but don't bother to digest the real info on a lot of these studies.

There are lots of them out there that are from lesser known people but these should stand up to scrutiny.

If you look hard enough you can find a study that proves just about anything is bad for you. Drinking water was a huge one I remember. But if you read the study you had to drink like 20 Litres in 10 mins.

People love the giant headlines but don't bother to digest the real info on a lot of these studies.

Thanks. I don't think the benefits of exercise is being disputed. I think what is being questioned is "how much is too much", and unfortunately for non-runners they seem to have a very low bar, and a marathon is considered "extreme"

O’Keefe said that many people misunderstand exercise and think more is always better. He points to his own patients - many are athletes who come in and say they are training for marathons, running several hours a day. O’Keefe tells them that it’s not good orthopedically.”

Who are these people?

Wing, are YOU running several hours per day?

"I want you to pray as if everything depends on it, but I want you to prepare yourself as if everything depends on you."

-- Dick LeBeau

northernman

Fight The Future

posted: 6/4/2012 at 12:41 PM

I would respond with these direct quotes from the Mayo Clinic Proceedings article your family member referred you to:

From the abstract:

long-term excessive sustained exercise may be associated with coronary artery calcification, diastolic dysfunction, and large-artery wall stiffening. However, this concept is still hypothetical and there is some inconsistency in the reported findings. Furthermore, lifelong vigorous exercisers generally have low mortality rates and excellent functional capacity.

People who exercise regularly have markedly lower rates of disability and a mean life expectancy that is 7 years longer than that of their physically inactive contemporaries. However, a safe upper-dose limit potentially exists, beyond which the adverse effects of exercise may outweigh its benefits.

All of the "badness" is hypothetical. The epidemiology that is solid is still in favor of exercise.

The Berkeley link above refers to the work of Paul Williams at LBL. He has done some of the studies closest to what you are looking for with some pretty large groups of people. This news article. More exercise better in long run, study finds,

may be suitable for sending to family members but here's the bottom line:

Williams' catalog of more than 100,000 runners has produced dozens of scientific and medical papers looking at the effect of running on everything from heart disease and stroke to vision problems and arthritis.

The more miles people run, the less likely they are to develop heart disease or have strokes, Williams has found. The health improvements continue up to about 50 miles a week of running, roughly eight hours. Williams, for the record, runs about 35 miles a week.

It's likely that health benefits keep growing above that level too - with the 100-mile-a-week runners, for example - but there aren't enough people in Williams' study running that much to provide hard data.